Sketching analysis design program

Researchers at PurdueUniversity have developed a type of design program that is said to bring analysis into the sketching stage of the design process.

The program allows the designer to sketch a rough concept of the part and then analyse its characteristics while it is still only a drawing, said Karthik Ramani, a professor of mechanical engineering at Purdue.

The concept, called FEAsy (finite-element analysis made easy), represents a departure from conventional design methods, in which engineers use finite-element analysis to test designs.

‘Ordinarily, the designer creates the component and then it has to go to other engineers who use specialised analysis software to test the design,’ said Ramani. ‘So the analysis gets done after many parts and systems are already designed and it’s too late to make major improvements or change design concepts at this stage.’

One major challenge is endowing the software code with the ability to distinguish the difference between lines, circles and arcs, as well as symbols such as arrows drawn by users to describe a part.

‘Say I’m a design engineer working for an automotive company and I want to find out how much stress my conceptual part can withstand,’ said Ramani. ‘I want to know where to drill the holes and what kind of materials to use. I might have hundreds of ideas on shapes and so on.’

The program automatically carries out steps including ‘geometric constraint solving’ and ‘primitive beautification’ to clean up the rough sketch.

‘The computer has to do what we call sketch understanding,’ continued Ramani. ‘If I don’t close a circle completely, the computer knows I mean to draw a circle and completes it. If I don’t draw lines exactly horizontal or perpendicular, the program recognises these flaws and corrects them.’

FEAsy then displays a formal version of the sketch and several alternatives for the designer to choose from. It also saves the original rough sketch.

‘Unlike other drawing programs on the market, you don’t have to use specific tools to draw circles and squares and lines,’ said Ramani. ‘You just draw and the computer understands what you are doing.’

FEAsy also is ‘domain independent’, meaning that it does not assume the part being drawn is for a specific end use, such as an electrical circuit or a bookshelf bracket.